Charge air coolers, often also referred to as intercoolers, are used to cool a stream of air that has been compressed by a turbocharger. When the air is compressed by the turbocharger, the air is heated and the pressure of the air is increased. However, it is desirable for the air entering the engine to be cooled after exiting the turbocharger because cooler air will have an increased density that improves the efficiency of the engine. The cooling of the air may also eliminate the danger of pre-detonation of the air and a fuel prior to a timed spark ignition.
Most charge air coolers include an inlet tank that distributes the air stream through a plurality of heat exchange tubes. A second cooling fluid flows over the plurality of heat exchange tubes and removes heat from the air flowing therethrough. The charge air then exits the plurality of heat exchange tubes and enters an outlet tank. The outlet tank includes a fluid outlet through which the air stream exits the charge air cooler before entering an intake region of the engine.
One problem associated with the charge air cooler is that water vapor included within the air stream may be caused to condense within the plurality of heat exchanger tubes when a temperature of the air stream is reduced. The resulting condensation may then flow through the outlet tank and be drawn into cylinders of the engine. The liquid water entering the cylinders may result in engine mis-fire and combustion issues that degrade the engine's performance.
Some prior art solutions to the problem of condensate formation within the charge air cooler have relied on drainage systems that include additional components and added complexity. Such drainage systems may for instance require additional plumbing extending from the charge air cooler to another component of the motor vehicle and additional components for monitoring, altering, or controlling the flow of either the air or the liquid water through the drainage system. In addition to potentially adding cost and complexity to the system, such drainage systems are often only suitable for very specific motor vehicles having predetermined operating conditions. Accordingly, the components used to form such a drainage system may not be suitable for use in another motor vehicle having different operating conditions, such as a different range of internal air pressures within the charge air cooler.
Additionally, such drainage systems may only be configured to drain the liquid water under very limited circumstances, such as when an internal pressure within the charge air cooler is above a threshold value. However, under some circumstances, the pressure of the air within the charge air cooler can actually drop suddenly to a pressure below the atmospheric pressure, creating a near vacuum within the charge air cooler. Many of the prior art drainage systems are not configured for operation during these limited circumstances.
It would therefore be desirable to produce a drain mechanism having a simple construction that is integrated into the charge air cooler and adjustable to the operating conditions of the motor vehicle having the charge air cooler.